G1- Series 0.4 hp At 0.4hp the G1-Series packs a lot of power in a small package G2 - Series 0.80 hp Perfect for big jobs, the G2-Series performs at an impressive 0.8 hp G3 - Series 1.35 hp For Superior power-to–weight ratio, delivering a mighty 1.35hp choose a G3-Series Grinder. Revolution 0.30 hp The Revolution Series offers a 0.3 hp at a reasonable price for the light industrial applications. Pro Series 61H 1.33 hp The powerful 1 1/3 hp Pro-Series motor produces high efficient performance. ARO 0.70 hp ARO rotary file tools running at 0.7 hp, designed for deburring.